To news that could affect your dinner hour, a move by a major american supermarket to reveal whether the food you're buying has been genetically modified. It happens far more often that many things. Here's abc's linzie janis. Reporter: These rows of brightly-colored fruits and vegetables are one of the reasons whole foods has developed a cultlike following. Tonight, quens whether the grocery chain's latest move could kick off a movement that other stores follow. Genetically-modified foods are produced by crops that have had specific changes to their dna. Often designed to make them grow faster. Now, whole foods is telling suppliers, if they're using gmo ingredients they need to say on the label. Customers are demanding the move. Even saying suppliers who advertise gmo free have seen sales increase. The u.S. Food and drug administration has long rule that so-called frankenfoods are safe and no different from other foods. Independent research backs that up. But will the move strike a chord with shoppers? I just think they don't know enough. Farmers were fine before they were genetically modified organisms. About 30% of processed foods has gmo ingredients in it. Tonight, david, even though the government said they're okay, not all consumers are convinced. Lots of question. The question is, will other markets follow suit?

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